According to a technique studied by the present inventors, drain structures used for both a field effect transistor of an input initial or first stage, which directly receives an input signal, and each of plural field effect transistors in a subsequent stage are identical to one another. Namely, semiconductor regions of conduction types opposite to conduction types of semiconductor regions for drains of both the field effect transistor of the input first stage and each of the field effect transistors in a subsequent stage are respectively provided in the neighborhood of the semiconductor regions for the drains of the field effect transistor of the input first stage and each of the field effect transistors of the subsequent stage to thereby suppress or prevent short channel effects. The gate length of the field effect transistor of the input first stage is made greater than the gate lengths of the field effect transistors of the subsequent stage to thereby ensure resistance to hot carriers and improve the life of the device with respect to its characteristic degeneration.